Conductor support



March l, 1932. I A, o, AUsTlN 1,847,461

CONDUCTOR SUPPQRT Filed Jan. y31, 1929 13Y%/Wt M ATTORNEY auf claims.

Patented Mar. l, 1932 i 1,841,46iv

. UNITED STATES. PATENT oFFIc-,E

ARTHUR- AUSTIN, 0T NEABBABBERTON, OHIOS` ASSIGNOIB, BY MESNEASSIGNMENTS,

T0 THE. 01H10 BRASS CGMPANY, 0F MANSFIELD, QEIO, A CORPORATIGN .0T NEW`JERSEY GONDUCTUR SUPPORT Application filed January 31, 1929. Serial No.336,57,5.

A further object is, to provide a cross arm which will withstand smallunbalanced longitudinal stresses in the conductor without displacementlbut which will yield to larger, unbalanced stresses'. f A furtherobject is to provide a cross. arm mounting suitable for a wood crossarmgand kwhich will permit maximum utilization of the insulatingproperties ofthe wood. A furtherobject isto provide a cross arm mountedto' swing upon its support but having vmeans for providing a limiteddegree of stability for withstanding small unbalanced stresses withoutmoving upon its pivotal support.V A further object is to providelv across arm support having spaced pivots which may be selectivelydisconnected but'which `cannot both be disconi nected simultaneously.`Other objects and advantages will appear from the following descriptionThe invention is exemplified in the combination and arrangement of partsshown in the accompanying drawings and described in the followingspecification, andv it is `.more particularly pointed out vin theappended In the drawings:

Figure 1' is a plan* view showing ,a'conduc-v torsupport embodying oneform of the present invention. i

Figure 2 is an elevation with parts in sec-` tion showing the supportof'Figure 1.

VFigure 3 is an elevation-looking from the f right' in Figure I withparts in section.

Figure 4 is a fragmentary' plan section showing a modifiedconstruction.`

Figure 5 is a. fragmentary' sectionl on line 545of'Fig. 2.-

In electrical transmission lines, it is ad-` visable to4 use highvoltageV for the sake of Y economy.` .This requires considerableinsula-Y tion. Where the line traverses districts sub*V ]ecttolightning, the transmission' line. may

also besubject to very high potentials produced by the lightning sothatthe transmis- Y sion conductors have to be insulated not only forthe voltage used in the transmission of power, but for the abnormalvoltage caused by lightning as well. In addition to these disturbances,lines are subject to switching surges. Another source of troubleon'transmission lines is due to birds.

Where the excessive voltages tending to cause liashover occur at a highfrequency or with a steep wave front, or where the duration of thestress is exceedingly short, material which will `ordinarily notinsulate the line may be quite effective. By using insulators such as`porcelain to carry the` normal voltage, it is possible to support theseinsulators from wood cross arms so that for abnormal surges ortransients theiiashover voltage will be greatly increased. In many casesthe flashover voltage of the insulator may be more than doubled byVmounting it on a wood cross arm.

Where the mechanical Vloads are light-V Wood has been effectively usedto afford high flashover voltage so as to'prevent arcs toA ground. Wherethe mechanical loads are heavy, however, the problem of supplyingsuiicient mechanical strength in the wood is more diilicult,particularly where clearance is an important factor` Inmy presentinvention it is possible to take advantage of Y the great increase inashover voltage due' to theuse of wood and at the same time eliminate to'a very large degree the mechanical limitations of the wood itself. Itis also possible to increase the insulation furnished by the woodmembers without increasing the mechanical loads upon the towers orV mainsupporting structure to which the cross arms are attached. l A

A cross arm having wood members lO'is provided with endrfittings Il towhich an insulator string 12V is attached.VV The cross -which the woodmembers rest. Themenliber 16 is provided with pinsl( and 18 which fitinto slots 19 and 20 respectively in :plates 21secured'to'one ofthetower members'22.

varms are attached to a vertical channel 13 by suitable bolts 14. Thevertical member 13' -95 The wood members 10 are extended back into thebasket of the tower and secured together by a spacer member 23. rlhemember 23 is attached to angle bars 2a, which are connected to the mainchannel member 13, and to brace 25 the upper end of which is secured tochannel member 13.

The object of the several members 24 and 25 together with the member 13is to form a rigid structure which will support the mechanical loadimposed upon the arm b v the insulator string 12. The channel member 13is secured to and supported by a pin 26 which takes the vertical loadproduced by the arm and furnishes an axis or rotation. lith thisarrangement it is possible to utilize practically the entire lena'th ot'the arm projecting bevond the tace of the tower Ytor insulation as themain bracing; is placed inside the tower, although it is evident thatthis bracing;l could be applied outside ot' the face of the towerequally as well from a mechanical standpoint which would permit the useof a short-er arm, but would cut down the insulation for a givenextension of the arm bevond the face oit the tower. The pin 26 issupported at its upper end by a rounded head 27, the pin being passedthrough a perforation in a flange 28 secured to the tower and the headbeing arranged to permit rotation of the pin and also limited transverseswinging in all directions as will be more apparent from Fig. 5.

Vith the arrangement shown in Fing. 1, the small unbalanced longitudinalloa-ds in the conductor will produce no movement o1 the cross arm but itis necessary that the nnbalanced longitudinal stress be sufficient torelieve the horizontal component on one of the pins 17 and 18 beforerotation ot the cross arm on its pivot-al support can start. Thedownward component produced by the weight of the insulator and conductoras well as the arm tends to produce a horizontal component actinginwardly toward the face et' the tower. Since the pins 17 and 18 arespaced well apart, they are capable oi3 setting up a considerable momentwhich will tend to resist rotation oli the arm. When. however, theunbalanced longitudinal pull ot this conductor becomes sufficient toover come the inward component on one ot the pins 17 or 18, the crossarm will tend to rotate toward the position shownin broken lines inFigs. 1 and 3. Such rotation takes place about an axis extending fromtheupper end of pin 26 to pin 17 or 18 depending;r on the direction ofrotation. Since the line joining the upper end of the pin 26 with thepin 18 is inclined, as will be apparent from Fig. 3, the arm 10 willswing about an inclined axis which willV tip the outer end of the armupwardly as it swings. The lower end of the supporting' pin 26 is spacedfrom the lower end 18 of the inclined axis of' rotation so that thelower end ol.l the pin 26 will swing outwardly and laterally toward theposition 26, Fig. 1, and the pin 26 will swing toward the position 26,Fig. 3. The upper end of the pin 26, as explained above, is supported inthc liange 28 in a manner to permit the transverse swinging: movementimparted to the pin 2G.

If a very heavy unbalanced load exists. the arm may be rotated entirelyinto the position shown in broken lines. llc't'orc reachinsr thisposition however, the thrust on the pin 18 becomes parallel with theface ot the tower. The slot in the lower plate permits the pin to moveinto the position 18 where it will be arrested by a stop 29. The weightot the arm and conductor will tend to hold the pin ti nhtlv in thisposition an d owingV to the shape o'l1 the stop 20. it will not bepossible for the pin to jump out and tberebv lose the bene'lit of thelower bearing. This is quite important tor it the cross a m swingsagainst the face ot the tower. the momentum mi vht readily force the pinout of the slot. Il the unbalanced longitudinal stress is relieved. thearm will tend to assume its normal. position. as the relation ot thebearii'lgrs is such that the outer end oiE the arm is raised materiallyir beiner thrown out of normal position. Bv properly spacingr the braeiner members in the tower with respect to the location of the crossarm. it is possible to utilize practically the entire portion extending4from the 'Face ot the tower for insulatinapurposes and. at the sa metime` use a portion extending: into the tower for gripping the woodmembers. 7h ere the portion inside the tower has the proper relation inrenard to the opening.lm in the tace ot the tower. it is possible topermit this portion to swine; ont through the opening without comin;r incontact with any olf' the tower members. It will be seen that with thistype of construction it is possible to use long arms and. at the sametime. limit the torsional stress imposed upon the tower. As the armswings. tho tension in the conductor is greatly reduced and the towerrelieved ot the stress which may save it from destruction owingr to thebreaking' of the conductor or to heavy sleet loads. The construction hasthe further advantage that the arm does not oscillate with any slightchange in load, making it difficult to work upon the arm. Theconstruction is such that it may be applied to many existing structuresto improve the ei'iective insulation, particularly from lightning; or toeliminate bird trouble.

The general construction is equally suitable for steel arms as well aswood arms. There are a number of ways of producing the equivalentresults embodying the above principles. The invention makes it possibleto take advantage of 'tl ne rigid arm and the swine` ti.. arm and alsopermits utilizing the insulation lut ICL'

lll,

55 of said pivotal connections being spaced from each other in adirection transverse to their to a lmaximum for a given clearancebetween the conductor and tower body.

In the modification shown inv Figure 4, the plate is usedin place of theplate 21 and is provided with slots 31 having enlarged circularopeningsv 32 at the inner ends thereof. Each slot- 31 is arranged in vanarc struck about the center of the opposite enlarged will be swung outof, its slot to permitv the cross arm to swing into the direction of thepull on the line. i i

Y Iclaim:

1. In combination a supportingstr'ucture,

a. cross .arm mounted onisaidstructure, ay

' transmission linecarried by said cross arm,

said cross arm beingpivoted tomovefin thel directionof the transmissionline under 1inbalancedload and having horizontally spaced.

pivotal points about one of which said cross arm swings when moved Vinthe direction of the transmission line. 4 j

2. Aconductor nsupport comprising a supportingstructure'l cross armmounted on said structure and two f sets of .pivotal connections betweensaid cross arm and said lsupporting structure, said Apivotal connections.provid-` ing different axes of rotation for said cross arm, said crossarm being arranged tofswing in-opposite directions about said differentaxes in rotationrespectively.

A conductor supportcomprising a, supporting. structure. a cross larmmounted -on said structure and arranged to Swingin op` posite directionsfrom an initial ,position about different axesof rotation, said axes ofrotation being inclined to the vertical to cause the supporting end ofthe cross arm to rise` when rotated in either direction.

4. In combination a supporting structure,

a cross arm mounted on said structure and having a conductor carried atthe outerend thereof, said cross arm having three points of pivotalconnection with said structure, two

pivotal axes.

5. In combination a supporting structure, a cross arm mounted on saidstructure, a pair of pivotal connections between said cross arm and thestructure, about which said cross arm;

is arranged to swing selectively, depending Vupon the direction .ofmovement of said cross arm, each coniiection'being arranged to sepagrate kwhen, said cross arm swings aboutthe other connection.

6. In combinationa supporting structure, a cross arm mounted on saidstructure,a pivotal connection between said cross arm-` an structure andtwo supplementary, separable,

pivotal connections-between said cross arm and structure, said:supplementary connections being spaced from eachother in a directiontransverse to the axis of said first named pivotal connection, each of-said supplementary pivotal connections being arranged to becomedetachedI when said ,cross arm is swung upon said supporting structureabout the other supplementary pivotal connection..

7. In combination a supporting structure,

a cross arm mounted on said structure, a pivf otal connection betweensaid cross arm and structure, twosupplem'entary pivotal connectionsbetween said crossarm and structure,

`said supplementary pivotaly connections bcing spaced at opposite sidesof the axesof rof tation of said rst named pivotal connection, each ofsaid supplementary pivotal connections being arranged to separate whensaidl cross arm swings about the other supplementary pivotal vconnectionand meansv for preventing separation of each of said'supple- Iiientarypivotal .connections when acting as the pivot about which said cross armswings.

: 8.`In combination a supportingl structure,

a cross arml mounted on said structure, a piv-V otal support .for saidcrossarm, a pair of spaced pin and slot connectionsbetween said crossarm and structure, each slot bein arranged to permit its pin to'escapethere rom when said cross arm'is swung about the other' pinas a pivotand-meansfor preventing escapev of each pin from its slot when the crossarm is swung about that pin as a pivot.

9.,In combination a supporting tower, a'.

cross arm pivotally mounted on ysaid tower at one. side thereof,said-cross arm projecting into the interior of said tower beyond said`p-ivotal support, and bracing means for saidcross arm connected withtheinwardly pro- Jecting portion thereof, and disposed within y the contourof said tower for norma-1 position of said cross arm', saidinwardlyprojecting portion and bracing means being arranged to swingvthrough` the sideof said tower when saidk cross arm is swung upon itspivotal supportf"k 10. l Incombination a supporting structure, a crossarm carried by said. structure and hav- `inghorizontally spaced pivotalconnections therewith, each ofsaid connections being separable to permithorizontal pivotal movement of said 'cross arm about the otherconnection, andmeans ,for preventing separation' of one ofsaidconnectionswhen said cross arm is swung about that connection awayfromnon mal-position.

I n` combination a. supporting structure,y a bearing means` mountedonsaidstructure,

'zeV

iio

and havingl horizontallyspaced pivot`fslots-, a cross arm, spaced pivotpins mounted onfsaidf c-rossarm anduingaging-said slots, eachV ol saidpins being 'vniovable` outwardly through its Yslot'lwhen"saidfcross armis swung about theotlicrpin, and means -for preventing escape ofa-pinfrom -itsslotwh'en said cross arm is'niovedfafbout that` pin awayifromits normal position.

12. Iny combination, a supporting tower, a cross-armA extending awayfrom said tower, a conductor carried by said cross aim, apivotalfconnection between said cross arm and tower disposedsubstantially in the central vertical plane of said cross arm, braceseX- tending laterally Jfrom said cross arm and, havingpivotalconnections with said tower at opposite'sides of the centralvertical plane of said `cross arm, each of said pivotal connectionsbeing arranged to permit outward movement of the bracerconnectedtherewith when said cross arm is rotated toward the side thereofadjacent the other pivotal connection.

13. In combination a skeleton tower, a wood cross arm projecting awayfrom said tower and having the inner end thereof ex` tending into theinterior of saidtower, metal bracing for said crossarm connected withthe portion thereof extending into the interior of said tower, a pivotalsupport for said crossarm disposed substantially'in the centralvertical'plane of said cross arm, and means fixedl to said cross armatopposite sides of'thecentral vertical plane thereof having pivotalcontact with said tower and held in engagement with said' tower andforming pivotal connection between said cross arm and-'said tower bytheweight of said cross arm for stabilizing said cross arm in its normalcentral position but arranged to permit pivotal movement of said crossarm when'subjected'to a transverse unbalanced Iload of predeterminedminimum magnitude.

14. In combination a supporting tower, a`

"wood cross arm movably supported on said tower, said cross arm having aportion thereof extending into the interior of said tower, and metallicbracing for said cross arm, said bracing holding said cross arm againstvertical inovement and being disposed within the interior of said towertopermit maximum utilization of the insulating properties of the portionof the cross arm projectingbeyond the tower;

16. In combination a lsupporting tower, a cross `arm movably mountedV onsaid tower, horizontally spaced pivots for said cross arm, said crossarm being arranged to swing about one of said pivots when moved in onedirectionfrom its normal position and to swing about the other of saidpivots when moved in the opposite direction from its normal position,and means arranged to be brought into operation by the movement of saidcross arm for locking against transverse displacement, the pivot aboutwhich said cross arm is swung.

17 In combination a supporting tower, a cross arm movably mounted onsaid tower, horizontally spaced pivots for said cross arm, said crossarm being arranged to swing about one of said pivots when moved'in onedirection from its normal position and to swing aboutthe other of saidpivots when moved in the opposite direction from its normal position,and means automatically operated by the pivotal movement of said crossarm for locking against transverse displacement, the pivot about whichsaid cross arm is swung.

18. In combination a supporting tower, a cross arm movably mounted onsaid tower, horizontally spaced pivots for said cross arm, said crossarm being arranged to swing about one of said pivots when moved in onedirection from its normal position and to swing about the other oi saidpivots when moved in the opposite direction from its normal position,and means operated by a. movement of said cross arm, additional to itspivotal movement, for locking against transverse displacement, the pivotpin about which said' cross arm is swung.

In testimony whereof I have signed my name to this specification this29th day of January A. D. 1929.

ARTHUR O. AUSTIN.

